Paediatric autoimmune thyroiditis triggered by prior SARS-CoV-2 exposure: a case with transient hashitoxicosis

Post-viral thyroid dysfunction, including autoimmune thyroiditis, may occur after severe acute respiratory syndrome coronavirus 2 infection even in children and should be considered in the differential diagnosis of prolonged febrile or inflammatory syndromes.Hashitoxicosis represents a transient destructive phase of autoimmune thyroiditis and can mimic subacute thyroiditis or other causes of thyrotoxicosis; ultrasound vascularity and antibody profile help differentiate them.Systemic inflammation with hepatic cytolysis or cytopenias may accompany autoimmune thyroid involvement, reflecting multi-organ immune activation rather than isolated endocrine disease.Thyroid function testing (thyroid-stimulating hormone, free thyroxine, antibodies) should be included in the evaluation of patients, children or adults, with unexplained post-viral symptoms or abnormal inflammatory profiles.